In the
general election of July 1977 the head of the list was
Javier Erice, who had been mayor of
Pamplona for a few months in 1976, until he was dismissed by the civil governor. UNAI brought together the majority of the left-wing
Basque nationalist vote in
Navarre, obtaining the 9.47% of the total vote and becoming the third political force in the province.[2] Despite this relative success, the 24,489 votes were not enough to gain a deputy in the Constituent Parliament (
UCD obtained three deputies and the
PSE-PSOE the other two). UNAI also failed to gain representation in the
Senate.

UNAI sent Jesus Urra to the commission that prepared the 1977 pre-autonomic agreement; this caused several activists of
Euskadiko Ezkerra, that were against supporting any autonomic agreement that didn't include the
KAS Alternative, to leave the coalition and join the newly formed
Herri Batasuna (HB). UNAI was more affected more by this split than
Euskadiko Ezkerra. Also, due to discrepancies over this issue,
EMK[3] and
EIA left the coalition. Furthermore, in December 1978, the
ORT was "expelled" for registering the initials of the coalition.[4] In practice, that meant that only the ORT could use that acronym, and that the rest of parties had been de facto expelled from UNAI.

In the
general elections of March 1979, with a fully controlled by the ORT candidacy, the head of the list was José Miguel Ibarrola (secretary general of the
Sindicato Unitario). UNAI got 10,970 votes (4.34% of the total), far from obtaining any representation. Meanwhile,
OIC-EKE and the EMK had just completed its convergence and presented their own candidacy, that obtained 2,962 votes (1.17% of the total).